Keep your eye on the ball: Local versus global statistics in sport visualisation

Abstract

This paper describes several simple local space-time statistical measures that can be applied to data that describes ball position over space and time. The main aim is to show that global statistics of rugby union do not describe the most important aspects of team domination, and that other measures may be more meaningful in terms of understanding the overall patterns of play. This paper introduces several measures for describing these local statistics, and shows for one example that they reflect the dominance of one team even though this is not reflected in the half-time score. The main conclusion is that the most important local statistics maintain an explicit spatial representation, and that therefore global measures of behaviour, that have removed the spatial patterns of play, are not appropriate descriptors for rugby union.